As a technology of registering an unregistered road into a map database, patent reference 1 discloses a navigation apparatus which, when a vehicle passes through a road whose information is not included in its road information, holds the information and registers, as a new road, the road therein to enable navigation without waiting for an update or revision of a CD-ROM having the road information. This navigation apparatus is provided with a GPS receiving unit, a display unit for displaying the vehicle position, a CD-ROM drive unit for reading data from the CD-ROM which stores the map information, and a control unit having a road information storage memory, and converts track data about the vehicle into straight lines and nodes when detecting a departure of the vehicle position from any road whose information is included in the road information stored in the CD-ROM or according to a command input by a user, starts storing them in the road information memory, and, when the vehicle position returns to a road whose information is included in the road information stored in the CD-ROM or when ending the storing operation according to the user's specification, registers the track data about the vehicle as a new road.
Patent reference 2 discloses a navigation system which can perform an addition, a deletion, a change, and so on of data on existing map information. This navigation system displays a map on the basis of the map information and searches for a route to a destination and performs route guidance, and is provided with a reference point setting means for setting up a plurality of reference points each of which is a starting point or an end point of a road, a position detecting means for detecting the position of a vehicle, a map information generating means for generating road information on the basis of the position information detected by the position detecting means when the vehicle moves from a first reference point which is one of the plurality of reference points to a different second point by way of a road whose information is not included in the map information, and an additional map information storage means for storing the road information generated by the map information generating means as a part of the map information.    [Patent reference 1] JP,8-271272,A    [Patent reference 2] JP,2001-74485,A
However, because the navigation apparatus shown in above-mentioned patent reference 1 compares roads shown by the road information with the vehicle position, and sequentially stores the track data about the vehicle in the road information memory while carrying out map matching of modifying the vehicle position in such a way that the vehicle position is located on a road, when the vehicle is running along an unregistered road, the navigation apparatus enters a state in which the navigation apparatus provides erroneous map matching between the vehicle position and a road in the vicinity of the unregistered road, and therefore cannot store correct track data about the unregistered road in the road information memory. As a result, there arises a problem that correct data about an unregistered road cannot be acquired.
The navigation system disclosed by patent reference 2 presets up a plurality of reference points each of which is a starting point or an end point of a road, and, when the vehicle moves from one of the plurality of reference points to a different reference point by way of a road whose information is not included in the map information, generates road information on the basis of position information detected, and stores the generated road information as a part of the map information. A problem is therefore that a case in which any reference point which is set up beforehand does not match the start point or the end point of an unregistered road correctly occurs, and correct data about an unregistered road cannot be acquired.
The present invention is made in order to solve the above-mentioned problems, and it is therefore an object of the present invention to provide a map information processing apparatus which can acquire correct data about an unregistered road and can add the unregistered road to map information.